Fermented Foods and How Kombucha Benefits Your Health

Fermented foods like kombucha are known for their distinctive taste and health benefits. Learn how to make kombucha at home.

A large kombucha in a glass jar, a small glass containing kombucha and a bowl of raspberries on a wooden table

Fermented foods have been consumed in various countries and cultures across the globe for hundreds or even thousands of years. There are many types of fermented foods that stand the test of time. One, in particular, is kombucha, a fermented tea usually made using black tea or green tea. Many people rave about kombucha benefits, but is it worth becoming your staple morning beverage? 

All fermented foods — including kombucha — are similar. They undergo microbial growth that results in a slightly acidic taste. During the fermentation process, microorganisms such as yeast and bacteria break down food components into other products, including organic acids, gases or alcohol. 

As kombucha is a by-product of tea, it is safe to say that tea and kombucha have similar benefits. However, kombucha is also rich in beneficial probiotics. More importantly, it contains antioxidants which may help eliminate harmful bacteria and fight against some diseases. Let’s dive in to know more about the health benefits of this ancient fermented drink. 

Benefits of Consuming Kombucha

A young girl is holding a glass of kombucha
When brewed properly, kombucha can be an enjoyable health drink. 

Kombucha is a traditional drink that originated from Northeast China around 220 B.C. Due to its healing properties, the drink was presented as a gift to the Japanese emperor and brought to Europe as a trade item. “Some call kombucha the elixir of life, and it can help remove toxins, aid spleen function, and balances qi. We also include ingredients like rooibos tea and ginseng tea in making kombucha,” says Traditional Chinese Medicine (TCM) physician Lim Sock Ling.

In ancient times, people would ferment fungi and malted grains to produce alcoholic beverages. There were ever records of wheat fermentation to create a medicine for treating diarrhoea during Spring and Autumn. Therefore, the popularity of kombucha is not without reason. Instead, there are scientific-based kombucha benefits that you should know.

1. A potential source of probiotics 

According to a 2020 paper published in the Journal of Functional Foods, kombucha is a probiotic drink that improves immunity and gut health. Probiotics can help treat or relieve diarrhoea, inflamed and irritable bowel. 

Bacteria and yeasts found in kombucha are potential probiotics, though there are minimal studies on the specific microorganisms present in kombucha. 

“Although there is still no concrete evidence for the probiotic benefits of kombucha, it contains several species of lactic-acid bacteria which may have probiotic functions. This can benefit people with digestive issues such as IBS and inflammation. It can also aid in weight loss. Medicated leaven (Liu Shen Qu) shares a similar function to promote digestion, relieve stasis and strengthen the spleen and stomach,” physician Lim adds.

2. Rich in antioxidants 

Kombucha is abundant in chemical and healthy properties. This includes organic acids, minerals and vitamins originating mainly from tea, amino acids, and biologically active compounds such as polyphenols.

Depending on which type of tea you use as your kombucha base, this drink is rich in antioxidants. By drinking it regularly, you may be able to slow down the ageing process not only for your skin but also for your brain health. One particular research notes that red and green tea are prominent antioxidants, especially polyphenols and flavonoids — perfect for making kombucha. 

3. May provide the benefits of the tea used 

Kombucha benefits derive from the tea used to brew it. Whether you’re using green tea, black tea, or rooibos tea, fermenting it into kombucha can maximise its health benefits. 

A 2018 study published in Nutrients shows a comparison between kombucha brewed with black, green and rooibos tea. Although antioxidant activity is higher in black and green kombucha compared to rooibos, the latter shows a predominant effect on the recovery from oxidative stress. These results make rooibos a potential candidate for the preparation of kombucha, especially to repair cells damage caused by pollutants and free radicals.

4. Fights infections 

There are reports of antibacterial and antifungal activities in kombucha prepared from green and black teas. In addition, the fermentation process makes acetic acid which has antimicrobial activities.

Kombucha may help your body fight off bacteria that cause infections like skin inflammation, food poisoning, and pneumonia. Research states that kombucha can be an alternative to current synthetic antimicrobial drugs. 

5. Maintains a healthy heart 

A study in 2018 reports kombucha consumption can protect against the development of cardiovascular diseases. Kombucha has high polyphenol content that prevents oxidation of low-density lipoproteins (LDL), regulates cholesterol metabolism, and maintain normal blood pressure by inducing smooth muscle relaxation. For your heart health, be sure to follow mindful eating habits and regular exercise. 

6. Manages type 2 diabetes 

Glucuronic acid (GlcUA), one of the main components in kombucha, helps to enhance liver functions. Furthermore, kombucha is a good inhibitor of high pancreatic amylase that suppress the absorption of glucose.

However, the concentration of the drink’s active components will vary depending on the Symbiotic Culture of Bacteria and Yeast (SCOBY) that you use and elaboration methods during fermentation. 

7. Helps protect against cancer 

In a 2019 study on the effects of kombucha on colorectal cancer, kombucha tea may have the ability to prevent cancer, particularly in the digestive system. The phenolic acid and antioxidants found in kombucha prove to be selectively toxic on colorectal cancer cells. 

How to Brew Kombucha at Home

Kombucha in two jars next to ginger, star anise, cinnamon sticks and dried figs on a table
Besides brewing kombucha with tea, you can add beneficial herbs and spices.

You can make kombucha by mixing tea (black, green, red, or white) with sugar and other ingredients and fermenting at room temperature for 7-14 days with a SCOBY (a specific mix of yeast and bacteria). 

Kombucha tea recipe 

Ingredients

  • 1.6 L Clean water 
  • 100 g Sugar 
  • 4 bags Black, green, red or white tea (or 1 tablespoon loose leaf tea) 
  • 8 bags Herbs (optional) 
  • 1 Kombucha SCOBY 
  • 1 large glass or ceramic jar 
  • 1 piece of cloth big enough to cover the top of the jar  
  • 1 rubber band  

Method

  1. Bring water to a boil and dissolve the sugar in it.
  2. Add the tea to steep while the water cools down.
  3. Pour the cooled tea into the jar and add the kombucha SCOBY on top.
  4. Cover the jar with the cloth and use the rubber band to hold it in place.
  5. Set the jar in a cool and dry place for 7-14 days.
  6. Begin tasting the tea at 7 days. The longer it ferments, the more sugar is used, producing a less sweet beverage. 

“You can add herbs into your kombucha tea as well. Herbs should be freshly cut into smaller pieces or powdered and placed in a teabag before use. The amount of herbal tea used should be twice that of common tea,” says physician Lim.

Physician Lim also suggests using rooibos tea and ginseng tea to brew kombucha for added health benefits. 

Side Effects 

Kombucha may cause some side effects, which might be due to unhygienic conditions and improper use of utensils in its preparation. 

“Since the mid-1990s, several cases of illness and at least one death have been reported in people who drank kombucha. Ailments included liver problems, lactic acidosis (a buildup of lactic acid in the body), allergic reactions, and nausea,” explains physician Lim.

“If the fermentation process is not effectively managed, the alcohol content may be higher than expected. In addition, making kombucha involves growing bacteria in the liquid you are going to drink. If it is not sterile, it can grow harmful bacteria or mould,” she adds.

Thus, it is important to ensure all utensils and containers used have been properly washed and cleaned with detergent and dried with a clean cloth before use. Also, kombucha should not be brewed in containers that have toxic chemicals, such as the lead in pottery glazes. These chemicals can get into the kombucha and cause side effects or poisoning. 

Who Should Avoid Kombucha 

Physician Lim advises the elderly and individuals with compromised immune systems to avoid homebrews as they are not pasteurised. Besides that, pregnant and breastfeeding women and individuals with known allergies to alcohol should avoid it.

In addition, diabetic patients should consume with caution or seek a medical professional’s advice before consumption. This is because kombucha may affect blood sugar levels in people with diabetes and cause low blood sugar.

Always consult a medical professional or TCM physician before drinking kombucha, especially if you have a health condition. They can help guide you on when and how to consume kombucha. Lastly, obtain SCOBY from others who have successfully brewed kombucha. With the right SCOBY and tea of your choosing, you can try making the recipe and enjoy kombucha benefits at home.

References

  1. Antioxidants (Basel). 2020. Chemical Profile and Antioxidant Activity of the Kombucha Beverage Derived from White, Green, Black and Red Tea.  [Accessed on 29 December 2021] 
  2. CyTA – Journal of Food. 2018. A review on health benefits of kombucha nutritional compounds and metabolites. [Accessed on 29 December 2021] 
  3. Journal of Food Biochemistry. 2012. Antibacterial and Antifungal Activities of Black and Green Kombucha Teas.  [Accessed on 29 December 2021] 
  4. Journal of Functional Foods. 2020. Probiotic potential of kombucha.  [Accessed on 29 December 2021] 
  5. Microorganisms. 2019. Efficacy of Kombucha Obtained from Green, Oolong, and Black Teas on Inhibition of Pathogenic Bacteria, Antioxidation, and Toxicity on Colorectal Cancer Cell Line. [Accessed on 29 December 2021] 
  6. Nutrients. 2018. Kombucha Beverage from Green, Black and Rooibos Teas: A Comparative Study Looking at Microbiology, Chemistry and Antioxidant Activity.  [Accessed on 29 December 2021] 
  7. Annals of Epidemiology. 2019. Kombucha: a systematic review of the empirical evidence of human health benefit.
  8. BMC Complement Altern Med. 2012. Hypoglycemic and antilipidemic properties of kombucha tea in alloxan-induced diabetic rats.
  9. National Center for Complementary and Integrative Health. 2019. Probiotics: What You Need To Know.

Related Articles

The contents of the All Things Health website are for informational and educational purposes only.
Our website is not intended to be a substitute for professional medical advice, diagnosis, or treatment.